Two M>8 earthquakes (15/11/2006 and 13/01/2007) in Kurils Islands
within less than 60 days and less than 100 km

Two large events (Mw 8.3 and Mw 8.2) distant of less than 100 km occurred in the Kurils Islands within less than 60 days (on 15/11/2006 at 11:14 GMT and on 13/01/2007 at 04:23 GMT).

The 2 events present :

Different focal mechanisms: Normal fault on 13/01 and Thrust on 15/11.

Very different aftershocks distribution patterns with almost twice as many aftershocks after the 15/11 event than after the 13/01 event. A lack of large event for after the 13/01 event.

A distribution pattern which covers a 200km wide area for the 15/11 event whereas the aftershocks are mainly distributed on one side of the trench for the 13/01 event. While for the November 15th event, the aftershock epicenters were spread over an area of roughly 400x200km encompassing both plates, the first 3 days of aftershock activity for the January 13th event are spread over a more limited region (300x100km) and seem to be localised in their vast majority within the subducted plate.

Main shock

Information about the tsunami

Time and magnitude distribution of aftershocks of the 15/11/2006 event

Time and magnitude distribution of aftershocks of the 13/01/2007 event

Mw 8.3 on 15/11/2006

From 15/11 to 20/11, the EMSC recorded more than 134 aftershocks of magnitude greater than 4.0, 79 with M>5 (see day by day distribution). The aftershocks are mainly distributed North-East of the Main shock on a distance of about 300 km (see Figure below).

An earthquake sequence has been observed in the same region from 26/09 to 04/10/2006 (6-7 weeks before the main shock).

Information about the tsunami

The effects of this earthquake were a surprise at the Crescent City Harbor (California) on 15/11/2006 afternoon, after a surge wave caused "extensive damage," according to the California Office of Emergency Services. An OES alert said the 6-foot surge wave at Crescent City came in at around 30 mph. Visit the University of Southern California web site for more information.